This application is based on application No. 058814 filed in Japan on Mar. 3, 2000, the content of which is incorporated hereinto by reference.
This invention relates to a cleaning tool for removing dirt and foreign material from optical fiber connectors to make them clean.
An optical fiber connector has a connecting surface exposed at its end. The optical fiber connector 41 shown in FIG. 1 has optical fiber fixed at the center of a zirconia ceramic ferrule 42, and its connecting surface 43 is polished to a mirror surface. Optical fiber connectors of this configuration are joined with connecting surfaces in mutual opposition to transmit optical signals. If the connecting surfaces are dirty or foreign material is attached to the connecting surfaces when a pair of optical fiber connectors are joined, optical signals cannot be transmitted properly. This is because a dirty surface or foreign particles will block or reflect light in the optical fiber.
To avoid this problem it is necessary to clean the connecting surfaces then join optical fiber connectors. The cleaning tool shown in FIG. 2 has been developed as a tool for cleaning optical fiber connectors (Japanese Laid-open Patent Publication TOKU-KAI-HEI 6-242,347, 1994). FIG. 3 shows the internal structure of the cleaning tool of FIG. 2 with the case 44 opened. As shown in FIG. 3, a cleaning sheet 4 is wound around pulley 47 in the form of tape inside the case 44. Cleaning sheet 4 is wound by operation of a lever 45 provided on the case 44, and it moves cleaning sheet 4 which is exposed in windows 46 through the case 44. Each time the lever 45 is operated, an unused portion of the cleaning sheet 4 is exposed in the windows 46. Therefore, an optical fiber connector connecting surface can be polished clean by rubbing the connecting surface against the cleaning sheet 4 that is exposed through the windows 46.
The cleaning tool shown in FIG. 2 is capable of cleaning optical fiber connecting surfaces with the cleaning sheet, but it limits operator""s hands to use it. The cleaning tool shown in FIG. 2 is arranged for use by operating the lever with the operator""s left hand thumb so that right-handers can use it. The structure of the cleaning tool is not capable of being operated by right hand for left-handers. It is a drawback that makes it difficult to use the tool by left-handers.
In addition, the cleaning tool shown FIG. 2 has another drawback in that the projecting lever from the case makes a storage outer case larger. Further, the cleaning tool shown in FIG. 2 has another drawback in that dirt and dust can enter into the case and then attach to the cleaning sheet, since the cleaning tool shown in FIG. 2 has an open circular arc shaped slit to permit rotation of the lever. If dirt attaches to the cleaning sheet, it can attach to a connecting surface when the optical fiber connector is rubbed against the cleaning sheet, and disrupt light transmission. In particular, dirt does not attach to the portion of the cleaning sheet which is wound tightly in a roll, but a portion of the cleaning sheet is unwound and exposed within the case for the purpose of transfer and delivery.
The present invention has been developed to further solve these types of problems and drawbacks. Thus, it is a primary object of the present invention to provide a cleaning tool for optical fiber connectors, which can be used by every operator conveniently, can be held compactly and has a structure that can prevent dirt and dust from entering into the case.
The above and further objects and features of the invention will more fully be apparent from the following detailed description along accompanying drawings.
The cleaning tool for optical fiber connectors of the present invention has a case formed in a box shape which exposes a part of a cleaning sheet disposed inside in a window for cleaning, a winding pulley for winding the cleaning sheet disposed inside of the case at a constant pitch, a rotating mechanism for rotating the winding pulley, and a lever for operating the rotating mechanism. Further, the cleaning tool of the present invention has the elements described below.
The case has a box-like form that is defined by a first front (side) plate and a second front (side) plate interconnected by a perimeter wall. The cleaning sheet and the winding pulley are disposed between the first front plate and the second front plate of the case. The case defines an open portion partially in the perimeter wall, and the lever is disposed in the open portion so as to be inclinable. The lever is attached to the case to be able to incline (pivot) about an incline axis perpendicular to the surfaces of the first front plate and the second front plate. Operating the lever rotates the winding pulley by the rotating mechanism, and winding the cleaning sheet of the winding pulley moves the cleaning sheet in the cleaning window.
The cleaning tool for optical fiber connectors described above has the advantageous feature that it can be used by every operator conveniently, regardless of whether they are right-handed or left-handed. The operators can hold the upper surface, which as the cleaning window, with their thumbs, and the bottom side with the other fingers. The case of the cleaning tool of the present invention, which is held in such manner for use, can be held either by the right hand or the left hand for use. In particular, the cleaning tool of the present invention has the feature that it can be used easily in comparison with the related art cleaning tool, since it is operated by holding the upper surface with the operator""s thumb and holding the lever with the other fingers, and not by holding the lever with operator""s thumb such as in the related art cleaning tool.
In addition, the cleaning tool for optical fiber connectors, as described above, has a further advantageous feature in that its overall width can be substantially the same as the case width, and it can be held in a more compact storage case or the like, since it is not necessary for the lever to project from the side of the case, as in the prior art cleaning tool, and the lever is disposed in the open window on the perimeter wall so as to be able to pivot.
Further, the cleaning tool for optical fiber connectors described above has the feature that it has the structure for closing off the open window in the perimeter wall by operation of the lever and thereby decreasing the dirt and dust that can enter into the case.